Create/Add view pagers programmatically

Question

I am having trouble creating and adding a view pager programmatically.

I have found this question Android create ViewPager programmatically but the accepted answer doesnt work for me.

Here is the relative code.

           ImagesPagerAdapter mImagePagerAdapter = new ImagesPagerAdapter(getActivity(), mProduct.getImages());
            ViewPager mImagePager = (ViewPager) inflater.inflate(R.layout.partial_view_pager, null);
            mImagePager.setAdapter(mImagePagerAdapter);
            rootView.add(mImagePager);

I have also tried modifying the second line to but no effect:

           ViewPager mImagePager = new ViewPager(getActivity());

The view pager just doesnt show up in the rendered layout. If i debug i can see that it instantiates the views but they just dont show. I have tried adding the id like suggested in the solution and also setting the id in layout partial_view_layout.

The only thing that seems to work is if i add the view pager through xml directly in the layout. This is not an option for me, since i want to be able to add multiple view pagers to the same layout.

Any ideas?

Check my answer for this post (http://stackoverflow.com/questions/28676491/how-to-dynamically-set-number-of-swipeable-tabs-in-action-bar-using-fragment/28679356#28679356) — Xcihnegn, Mar 08 '15 at 22:01
I don see how this answer relates to my question? I dont have trouble with dynamic number of tabs within an view pager, i want to add many view pager's to the layout so i will have many rows of swipeable content. — JanBo, Mar 09 '15 at 08:48
Have you tried setting an id (like `viewPager.setId(R.id.your_id)`) to viewpager? — waqaslam, Oct 05 '15 at 12:11

score 1 · Answer 1 · answered Feb 14 '18 at 17:33

Your question is an important one, it applies not only to ViewPagers but actually to the generic case: "how to create a view dynamically?"

Three steps:

setup the View object
setup the LayoutParams (so that the view can tell the layout what size it wants to be etc.)
Add it to the View hierarchy where you want it to appear

For a ViewPager there are a few details that you are missing:

// this is the container for the ViewPager
FrameLayout mRootView;
mRootView = (FrameLayout) findViewById(R.id.root_layout);

ViewPager viewPager = new ViewPager(this);

viewPager.setId(View.generateViewId()); // --> this is important!

viewPager.setAdapter(new CustomViewPagerAdapter(getSupportFragmentManager(), this));

// --> Important! * 
FrameLayout.LayoutParams params = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);

viewPager.setLayoutParams(params);

// --> Important!
mRootView.addView(viewPager, viewPager.getLayoutParams());

One final note, depending on the Layout that you are using you will have to change the LayoutParams that you use:

ie.

RelativeLayout -> RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(...)

LinearLayout -> LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(...)

Create/Add view pagers programmatically

1 Answers1